Dynamic simulation of metal transfer in GMAW, Part 2: Short-circuit transfer modes

Abstract

Short-circuit transfer is simulated dynamically by adopting the Volume of Fluid (VOF) method to analyze the effects of welding parameters on metal transfer. Appropriate initial and boundary conditions are imposed to simulate short-circuit transfer. The free surface profiles, pressure and velocity distributions are computed numerically during short-circuit transfer. The effects of the welding current, drop volume, contact area and wire feed rate on metal transfer are analyzed through variations of the pinch radius and break-up time. In the early stage of transfer, the molten metal in the bridge is transferred to the weld pool mainly due to the capillary pressure. The electromagnetic force becomes a dominant factor in the later stages of transfer. The effects of a current waveform on the characteristics of the metal transfer also are simulated.